This invention relates to down hole motors used in drilling oil and gas wells. More particularly, but not by way of limitation, this invention relates to a CV joint for a transmission used with down hole motors.
As the energy industry seeks new reserves, operators are drilling wells that are highly deviated and in many cases horizontal. The wells can be very deep and the speed in which wells are drilled is critical. The drill strings require highly complex designs and must withstand substantial torque, strain and weight, as well understood by those of ordinary skill in the art.
Prior art down hole motors require a constant velocity (“CV”) joint (sometimes referred to as universal joints) for the rotary transmission to the attached drill bit. See U.S. Pat. No. 4,772,246 to Wenzel, entitled “Downhole Motor Drive Shaft Universal Joint Assembly” which is incorporated in its entirety herein by express reference. In the event of a failure of the CV joint, drilling must be ceased and the entire drill string is pulled from the well for proper maintenance and/or repair.